I’m guessing it’s 2011 thing…
I actually hate doing this, it is not natural to do.. but sometimes the course of fire dictates to drop the magazine (for speed reload) with rounds in it.
Usually it ends up with loose rounds all over the place… but sometimes weird configuration happens… 
That second magazine, had you not dropped it, you would have shot your eye out. 
I learn the lesson long time ago when I developed weird malfunction using the mag previously dropped with ammo.
It never happened with any other magazine - only 2011 (specifically Staccato G3 120MM mag).
I really very rarely drop the mag with ammo with it… but once I do this I always check the top two rounds… 
Are they Checkmate magazines?
I have the same issues with my Checkmate magazines. I have heard stories about when the 2011 platform first came out that they had to uh adjust the feed lips.
Original G3 120MM magazines.
These are super reliable. I don’t remember if I had any issues with them since I bought the handgun in 2021.
The “dancing rounds” in dropped magazines is the only thing I notices. But… as mentioned before → I do not drop non-empty magazines unless it is a requested part of the drill.
